Universal constant speed joint



De.31,'193-5. Ef/WARD V '2,026,244-

UNIVERSAL CONSTANT SPEED JOINT Filed March lZ1, 1954 2 Sheecs-Shee?I l Patented 31, 193s f UNITED STATES PATENT o1=1=1cE UNrvnnsAL coNs'rAN'r srmin Jonsr'rA rancio amilo Hyun, rms, muco Application Mau-cn 31, 1934, scrisi'No. '118,415 In France April 6, 1933 5. Claims. (CL 641-21) The lpresent invention has as its subject a homokinetic transmission coupling which is particularly applicable to front wheel drive on selfpropelledvehiclf l- All the transmission couplings with closed pairs are characterized' (as the author of the `present invention was the first-to disclose and prove geometricall'y, see Le Genie Civil of the 15th April sin 10th June 1933) by the com- 10 binationof two pivot joints connectedby a flat nection to keep the two shafts to be joined inthe concurrent position and consequently sym- 80 metrical.

The said coupling forming the subject mat-l ter of the invention shows moreover-as compared with the other related couplings, great simplicity and extreme easeA of mechanical realization.

In this coupling the two shafts to be connected comprise at their ends facing one another (identical geometrically) pivot joints arranged similarly Vand provided with ilat parallel faces bearing against thel ilat faces of a member i0 `forming a 4f iat joint which is connected by a sliding element to la. balljoint the centreof which is the geometric point of intersection of the said shafts which abut on the otherhand against this ball.- DueV to this 4sliding connec- 85 tion between the ball constituting a ball joint and the member constituting a flat joint, this latter is maintained in space and cannot come Each pivot connection (pivot joint) may be ,'40 constituted in particular by c system of4 blocks or other members with flat parallel faces.- It is preferably by two blocks or turning membersv (the transverse section of which` is segmental)P located in Aa boring at theend of the shaft,

50 two pivot joints constituted preferably by two blocks the transverse section of which is segmental and may act by its external faces;

The ball forming `the ball joint according tp the invention may be constituted by two spherii 55 cal bearingsurfaceslocated voneachside of th'e 4s ingle plate of the fiat joint and so surrounds this plate, the two spherical bearing faces of the ball being. connected by a rod sliding in the said single plate of the flat joint. In any case as here above stated, the at joint and the ball 5 joint are connected together by` a sliding connection. y

Thus.- 4besides the combination of the two pivot joints and the flat joint (already known in close couplings with closed pairs) there ls 1o here, that is to say inthe coupling accordingto the invention, a ball joint (against whichthe two'shafts to be connected abut axially, which ensures symmetry from the start), and a sliding joint connecting the han joint to the said nat 15j joint formed of a single plate.

In -the accompanying rdrawings there are shown by way of non-limiting examplesvarious embodiments of thesubject of the invention.

V Inthese drawings: 20

Figures 1 and 2 show the coupling generally vand schematically, the two figures showing, it

for the same Obliquity in two positions of rotation diifering by a quarter turn.

Figure 3 shows a. coupling (in which the flat -2g; joint is substituted by a double plate/and the pivot blocks are made according to a` suitable variant) adapted for a front wheel drive system-.for motor cars.

Figure 4 is a horizontal section of the coupling `3o `forming the double plate, of the same.

Figure 6 is the transverse section of the stamped blank intended for making this double 35 -plate milling.

Figure 7 shows in perspective one of the pivoting.- systems with parallel faces corresponding to Figures 1 and 2 (system of two blocks nxed to a common pivot axis);v 40

Figures 8 and 9 show in orthogonal projection 'and gure 10 in perspective, one of the pivoting systems with parallelv faces in the case of the l coupling shownin Figures 3 and 4.?

Figui-osu and 12 showin longitudinal and 5^ transverse section respectivelyl one of the shafts to be connected comprising a pivoting .system with parallel faces constructed according to another variant. Y v

Figures 13 and 14 show in two successive positions of rotation differing by a quarter Mn the coupling according to the .invention in whichV Fre Figure 15 is a perspective view of the member constituting in this case half the pivot block.

Figure 16 is a modified construction of the ball in this case, in which the two spherical bearing surfaces and the connecting rod are made in one piece.

Figure 17 is a schematic representation of another variant of the coupling.

Referring to Figures 1 and 2, it will be seen that the ends of the two intersecting shafts a and a are geometrically identical and provided with pivots b and b' connected respectively to the pairs of blocks c1, cz and c1', c2'. The axes of the shafts a and a' meet at the point O which is the centre of a. sphere e upon which abut, by means of the spherical faces d and d', the two shafts a and a. A hole is drilled through this sphere e, in which slides a bar j which connects, perpendicularly to their plane and centrally to them, the two circular plates g1 and Ay2 with parallel faces. 'Ihe'two pivots b and b' form the twopivot joints and the flat joint is effected by means of two parallel plates g1 and g2 embracing the two pivotal systems with parallel faces and constraining the axes of the two pivots and it ensuresthat this assembly will be quite definitely maintained during rotation.

Figure 3 shows the cgupling adapted for a. front wheel drive system. The power is applied l to the shaft a which transmits it to the shaft a'.

'I'he mounting surrounding the coupling proper (forming the subject of the present invention), can be carried out in' many ways, either according to any of the orthodox methods for independent or other wheels, or in other ways. In the solution shwn in the drawings, the front axle h of the vehicle carries, bolted upon it, orpressed in one piece with it, the supporting arm h1. The cast hemispherical shell i is capped by the cover i bolted upon it along the diametrical plane A-.A and by -means of collarsl i1 and i1. Between these twoA membersV the two pivots and k are xed. 'I'he upper pivot 7' is subjected, by means of a Timken or other antifriction bearing (or simply by a at bearing surface), to a vertical downward thrust due to the weight of the vehicle. 'Ihe lower pivot k car- `not tilted with respect to the axis X-X. In

' practice the Wheel would be inclined upon the axis X-X.)

The spherical shell l enclosed in the housing formed by the shell i and the cover i'. It is connected by means. of suitable anti-friction bearingsv to the shaft a which is driven (as regards its rotary movement) either by a flexible coupling or`by a sliding Cardan shaft, or by any other suitable means. 'I'he iiexures of the suspension springs manifest themselves in a slightl pivoting of they assembly (shell l and shaft a) aroundy the horizontal -axis illustrated at the point O.

engages Vshafts .a and a', and in consequence a wider l0 steering ,lock easily reaching 40 and more degrecs without risk of the sphere e tending to escape from its housing) the member constituting the two plates g* and g2 can be made as follows: In a thick bar, or in a pressed member (Figure 15 6) two cuts are taken with a three cut milling cutter so as to form the two useful parallel faces leaving between them the two supports y, y (of curvilinear triangular section) which give the lgreatest strength for the least space occupied 20 (Figure 5). But numerous modifications are obviously possible for this double plate device.

The pivoting systems with parallel faces may thus have several embodiments. Thus the double blocks c1, c2 and c1 and cg' (Figures 1, 25 2 and 7) instead of being arranged so that their supporting pivoting axis (b or b') rotates in the corresponding shaft (as provided in the drawings), may on the contrary cap the two projecting ends of a stationary sleeved axis in the shaft, 30 and may pivot upon its projecting cylindrical bearing surfacesaxial stops then being coni veniently provided.

These pivoting systems with dat faces may also be set up as shown in Figures 3 and 4 and 35 in greater detail in Figures 8 to 10. This modiiication makes it possible to obtain good contact (thus a low unital pressure, low wear, and absence of seizing), a great strength and very reliable grip. In this modification everything oc- 40 curs as if the previous blocks c1, cz and c1 and c2 were connected respectively at c and c. To carry out the hollowing of these members a two cut milling cutter may be used, the corresponding limiting positions of which extend from Yi 45 to Y2 (Figure 8), or this may be carried out by boring.

Figures 11 and 12 show another possible arrangement in the construction of the pivoting members; c are constituted by a member of double T- shape connected to the shaft a by a supporting pivotal axis b.

In the modification of Figures 13 to 145 the two converging shafts a and a' each carryin a 55 geometrically identical way a circular cylindrical and open boring a1 and a'1 (that is to say, in the form of a fork) forming the housing of the corresponding pivot joint. The two pivot joints have as their geometric axes respectively the straight 60 lines X X arranged in a similar way and preferably each perpendicular to the corresponding shaft. Each pivot joint or pivot block is constituted by means of two identical members such as b, b or b', b' which are inserted in the open- 65 ing of the corresponding fork and placed against the walls of -its boring. Each piece b or b' has at its ends two collars or bearing cheeks which locate it axially.

The flat joint is constituted by means of the circular plate with at faces d which is housed in each fork between the two corresponding members b, b, and b', b. Its erectication is very convenient.

To make the members b, b' one may, for 75 In these gures the double blocks c, 50

provided, drawn to -the cross section of the -members b or b' these two bars, which are held by a mounting spaced at a distance apart equal to the thickness of the plate d (the flat surfaces being opposite) will then bev subjected, on their outer cylindrical operating faces either to a turning or machining operation on to theoircular o plate.

The ball, f which the two caps h. h. are connected together by the tie bar e.- serves as a stop4 for the two shafts a and a', each fork being provided for this purpose at its terminal zone with a corresponding spherical bearingv surface (sufaces aa and an'). This sphere thus causes the two shafts to meet-which in this particular case gives rise to symmetry and thus homokineticism. y.

In addition the fiat joint, constituted by the plate d, is connectedto the .ball Joint, constituted by the' ball 'h the centre 0, by

means of a sliding connection (also called sliding. pair or prismatic pair) constituted by the tie bar ve upon which the plate d slideswand is provided for this purpose with a corresponding boring. This connection ensures correct maintenance of the at joint system without which it would come adrift and-escape from its housing.`

Suitable grooves and ilats will in practi'ce be applied' to the parts to which they are appropri-v ate in order to economize space' (by the most compact assembly of the whole arrangement) and to allow large inclinations of the shafts c land a'y in relation to'each other. The drawings show these :dats and grooves (those at f and l" for example). It is obviousthat such a solution gives a robust coupling taking up little space and particularly easy to manufacture at small cost.

The thrusts are taken on -large surfaces which are not reduced in spite of varying inclinations (which give low unital pressure).

It is clear too that many other detailed modiileations as regards the distribution of material and shapes, grooves etc. can be made and form of course, part of .the invention. In thediameterofthetie'baremaybeincreased until it equals the base diameter of the cap h. In this case the'ntting allows (blockshhandbare) tobe-made inone piece -(Figure 16) which gives a greatmanufactin'lng advantage while ,reducing slightly the strength of Other modlflcations'arelikewise possible in he construction of the pivot blocks which may.l for example, be eachin the form of a` mortise and a single suitable"-piece.` .Modifications also.

intheformoftheb'allandthetiebararepossible (the htterbellig'lf of '(situatedupon-the outer part of the fork).

surface). and the tieb'ar.

'me .uw pieces which form .cap these surfaces, (each'one having a'conca swamp 3 According to another modification illustrated in Figure l'l the shaftsa, a' are nolonger each in the form'of an open fork, but the plate d is hollowed. f

I claim:

i. A coupling for connecting two shafts comprising identical pivot joints arranged at the ends of the shafts, said `ioints comprising yoke members integral with the shafts and two members having spaced apart parallel iiat surfaces 1o iournalledin each yoke member, a flat plate contacting the `said at faces of the members of the pivotioints and a sliding member passing through the center ofthe at plate and .con-v' nected at its ends to spherical segments the 15 center lof which is at-the point of intersection of the shafts, the spherical segments also bearing in spherical sockets formed on the yoke members.

2. A coupling for connecting two shafts com- 20 prislng identical pivot joints arranged at the ends of the shafts, said joints comprising yoke members integral with the shafts and two ,substantially semi-,cylindrical members having spaced apart parallel iiat surfaces journalled in each yoke member, a circular ilat plate con'- tacting the fiat faces of the semi-cylindrical members and a sliding lpin passing through the center of thecircular plate and provided atits ends with spherical segments the center of v which is at the point of intersection o f the U shafts, the sphericalscgments also bearing in spherical sockets formed on\the yoke members. 3. 4A coupling for connecting two shafts com-- prising` identical pivot joints arranged at vthesii ends 4of the shafts, said joints comprising yoke. membersintegral with theshafts and two members'having spaced apart parallel flat surfaces iournalled in -each yoke membera Vflat plateV A contacting the said ilat faces of the members of 40 the pivot Joints. and a sliding cylindrical pin through the center of jthe flat plate and provided at its ends with spherical segments integral-.therewith 1 Y v 4. A coupling for connecting two shafts com- 45 prising identical pivotjoints arranged at the ends of the shafts, said Joints comprising yoke members integral-with the shafts andtwo substaitialiy members provided .wlthgrooves and having spaced apart parallel 5o fiat surfaces joln'nalled in each yoke member, a flat plate contacting the saicifliiatfaces of the members of thepivot. joints -anda sliding memthe lcenter of the flat plate and at its ends to spherical segments the center of which is at the Vpoint of intersection of the-shafts, thespherical segments also bearing in spherical sockets formed on the yoke,

prising identical pivot joints arranged at-the ends ofthe shafts. said Joints comprising yOkG- members integral withthe shafts and two memr 5. A coupling forconnectlng two shafts com-.'00 

